TY JOUR TI RESEARCH OF MAIN CHARACTERISTICS OF SEMI-SUBMERSIBLE FLOATING DRILLING RIGS AT THE INITIAL STAGES OF DESIGN KW displacement KW pontoons KW stabilizing columns KW metacentric height KW vertical displacements JO Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies AU Ignatovich, V.. AU Kuzmina, A.. AU Rodkina, A.. PY 2018 IS PB Astrakhan State Technical University